Anchor bolt



TEIZO ONO Nov. 8, 1966 ANCHOR BOLT -2 Sheets-Sheet 1 Filed Feb. 10, 1965 Nov. 8, 1966 TEIZO ONO 3,283,640

OOOOOOOO LT Filed Feb. l0. 196 2 Sheets-Sheet 2 United States Patent 3,283,640 ANCHOR BOLT Teizo Ono, 32, 4-chome, Itachibori, Nishiku, Osaka, Japan Filed Feb. 10, 1965, Ser. No. 431,674 Claims priority, application Japan, June 20, 1964, 39/ 35,064 2 Claims. (Cl. 8569) This invention relates to an anchor bolt.

When it is intended to fix certain supports to concrete structures already constructed, it is customary to bore a hole in the concrete structure, insert an anchor bolt and then fill the clearance between the hole and the bolt with mortar, thereby to secure the bolt to the structure. However, this method has a disadvantage in that the clearance cannot be thoroughly filled with the mortar, and thereby the bolt cannot be tightly secured to the concrete structure. This is particularly the case on a horizontal surface such as a ceiling or the back side of a floor Where it is difficult to fill the surface with the mortar, and impossible to securely implant a bolt in a concrete structure.

It is contemplated by this invention to have a bolt held in the hole of a structure by screwing the bolt into an anchor and expanding expansible rings of the anchor outwardly within the bored hole thereby to fix the anchor securely within the inside surface of the hole, and therefore the anchor bolt provided by this invention is very simple in installation and yet is securely supported within the concrete structure irrespective of the simplicity in its installation.

An object of this invention is to provide an anchor bolt whereby a bolt is easily secured to the surface of a concrete structure irrespective of whether the surface is horizontal or vertical.

This invention will be more fully understood from the following detailed description given with reference to the appended drawings, in which:

FIG. 1 is an anchor bolt according to this invention;

FIG. 2 is a longitudinal sectional side view in part of a front ring;

FIG. 3 is a longitudinal sectional side view in part of a stop ring;

FIG. 4 is a front view of the foregoing stop ring;

FIG. 5 is a longitudinal sectional side view in part of an expansible ring;

FIG. 6 is a front view of the foregoing expansible ring;

FIG. 7 is a longitudinal sectional side view in part of of a nut ring;

FIGv 8 is a longitudinal sectional side view in part of a modification of a nut ring;

FIG. 9 is a longitudinal sectional side view of an expansible n'ng end to be used with the nut ring shown in FIG. 8;

FIG. 10 is a side view showing how an anchor bolt formed by combining the parts shown in FIGS. 27 is inserted in the hole of a concrete structure; and

FIG. 11 is a side view showing a bolt screwed through a support plate into the foregoing anchor shown in FIG. 10.

The anchor bolt provided by this invention basically comprises a bolt A and a combination of four parts constituted by a front ring B, a stop ring C, an expansible ring D and a nut ring E.

The bolt A is of an ordinary type, its length depending upon the sum total of the thickness of a support plate 2 and the depth of a hole 1.

The front ring B whose outside diameter is slightly smaller than the diameter of the hole 1 ha an inside 3,283,640 Patented Nov. 8, 1966 "ice diameter (d) to permit a bolt to pass through and has an inclined surface 3 inside in the rear part thereof.

The stop ring C has an inside diameter which permits a bolt to pass through and has numerous protrusions 4 provided on its outside periphery and inclined surfaces 5 and 6 extending from the protrusions 4. A flat ring 15 having protrusions 7 of the same shape and size as the protrusions 4 consisting of steel is secured to the front of the protrusions 4. This flat ring 15 may be dispensed with as the case may be. The said inclined surface 5 has the same inclination as the front ring B so that the former may be closely engaged with the inclined surface 3 of the latter.

The expansible ring D is formed at its rear part with an inside diameter (d), and at its front part with an inside inclined surface 8 conforming to the inclined surface 6. At the rear part of ring D of outside periphery has an inclined surface 9 conforming to said inclined surface 8, and extending forwardly therefrom are several lines of saw-toothed protrusions 18 and several parallel axial slits 11. This ring is used in a combination of three to four pieces.

The nut ring E is provided at its rear .part with an internal thread 12 to engage the bolt. In the front part at its outside periphery the ring E is provided with an inclined surface 13 conforming to the inclined surface 9 of the expansible ring D and also with protrusions 10 and slits 11.

A complete anchor is formed by suitably joining any number of expansible rings end to end between the stop ring combined with the front ring and nut ring according to the desired depth of the hole and by uniting them temporarily with each other with a weak binding agent. When the expansible anchor thus united into one piece is inserted in a hole, the protrusions 4 and 7 of the stop ring C catch the inlet of the hole and do not enter and the expansible anchor must be hammered strongly to force the stop ring to enter the hole, the protrusions being bent as shown in FIG. 9. Thus, the front surface of the front ring may reach the level of the surface of a concrete structure. But as the case may be, the flat ring 15 may be dispensed with, for the anchor may not at all slip out of the hole without the use of the flat ring 15 and protrusions.

Next, a bolt A is engaged in a hole 14 of a member to be supported from the concrete structure. The bolt A is then screwed into the threaded part 12 of the next ring E. When the bolt is turned, the ring E advances and, by the advancement of the ring E, all expansible rings D are advanced to push forward the stop ring C. The stop ring C however is prevented from moving forward by means of the protrusions 4. Further turning of the bolt cannot push the expansible being forward, thereby the rings are expanded outwardly of the slits 11 and the protrusions 10 rigidly and tightly engage the inside periphery of the hole, with the result that the expansible rings become integral with the concrete structure without any possibility of loosenting or slipping of the bolt whereby the bolt can securely hold the member to be supported. In short, this method has developed from the idea of engaging the expansible rings securely with the inside wall of the hole by causing the expansible rings to expand outwardly.

The foregoing expansible rings and nut ring are provided specifically with protrusions 10, but when the clearance between the inside periphery of the hole in the concrete structure and the outside periphery of the rings is very small, there is not only no need of providing the protrusions 10, but even the slits 11 in the nut ring may be omitted without substantial reduction in effect.

The nut ring may he used in the modified form as shown in FIGS. 8 and 9 in which are provided an inclined surface 16 on the outside periphery thereof and a threaded part 12 on the entire surface of the inside periphery t'hereof. If the ring in this case is made of material of the same quality as that of the bolt, engagement of the threaded parts become smooth, thereby giving the advantage of quick and suflicient advancement of the nut ring due to smooth screwing of the bolt. Also when such a nut ring is used, it becomes necessary to employ the special expansible ring as shown in FIG. 9 between the nut ring and the expansible rings. This special expansible ring is ditferent'frorn the foregoing expansible rings in that the inside periphery of the former is equipped on the side facing the nut ring with an inclined surface 17 conforming to the inclined surface 16 of the nut ling. The material for the foregoing rings may be soft or hard metal or synthetic resin in part as a substitute for metal.

What is claimed is:

1. An anchor adapted for being secured in a hole and engage a bolt, said anchor comprising a front ring, a stop ring, at least one expansible ring and a nut ring in that order in an axial arrangement, said front ring having a bore which at the end remote from the stop ring is cylindrical and at the end adjacent the stop ring is conical, said front ring having axial slits at the end adjacent the stop ring, said stop ring having an outer peripheral surface with oppositely tapering conical surfaces one of which matches the conical bore of the front ring to enter the same, and a radially enlarged intermediate portion with radially extending teeth, said expansible ring having a bore which at the end adjacent the stop ring is tapered and matches the other of the conical surfaces of the stop ring to receive the same, said expansible ring including an externally tapered portion at an end adjacent the nut ring and external protrusions extending towards the other end, said expansible ring being provided with slits extending axially from the end adjacent the stop ring towards the other end, said nut ring having an inner bore with a portion remote from the expansible ring which is threaded for engaging a bolt and a portion adjacent the expansible ring which is tapered to match the tapered portion of the expansi ble ring to receive the same, said nut ring having slits extending axially from the endadjacent the expansible ring towards its other end.

2. An anchor adapted for being secured in a hole and engage a bolt, said anchor comprising a front ring, a stop ring, at least one expansible ring and a nut ring in that order in an axial arrangement, said front ring having a bore which at the end remote from the stop ring is cylindrical and at the end adjacent the stop ring is conical, said front ring having axial slits at the end adjacent the stop ring, said stop ring having an outer peripheral surface with oppositely tapering conical surfaces one of which matches the conical bore of the front ring to enter the same, and a radially enlarged intermediate portion with radially extending teeth, said expansible ring having a bore which is tapered in opposite directions and at the end adjacent the stop ring has a taper which matches the other of the conical surfaces of the stop ring to receive the same, said expansible ring including external protrusions at the end adjacent the stop ring, said expansible ring having slits extending axially from the end adjacent the stop ring towards the other end, said nut ring having a cylindrical inner bore which is threaded and adapted for engaging a bolt, and a tapered outer surface Which matches the tapered surface of the bore at the adjacent end of the expansi ble ring to enter the same.

References Cited by the Examiner UNITED STATES PATENTS 665,705 1/ 1901 Summerer 85-69 1,120,408 12/1914 Rohmer et al. 85-67 1,120,657 12/1914 Roh-mer 85-74 2,139,167 12/1938 Marshall 8569 FOREIGN PATENTS 11,070 3/1902 Norway. 91,909 12/1937 Sweden.

CARL W. TOMLIN, Primary Examiner. EDWARD C. ALLEN, Examiner,

R. S. BRITT S, Assistant Examiner. 

1. AN ANCHOR ADAPTED FOR BEING SECURED IN A HOLE AND ENGAGE A BOLT, SAID ANCHOR COMPRISING A FRONT RING A STOP RING, AT LEAST ONE EXPANSIBLE RING AND A NUT RING IN THAT ORDER IN AN AXIAL ARRANGEMENT, SAID FRONT RING HAVING A BORE WHICH AT THE END REMOTE FROM THE STOP RING IS CYLINDRICAL AND AT THE END ADJACENT THE STOP RING IS CONICAL, SAID FRONT RING HAVING AXIAL SLITS AT THE END ADJACENT THE STOP RING, SAID STOP RING HAVING AN OUTER PERIPHERAL SURFACE WITH OPPOSITELY TAPERING CONICAL SURFACES ONE OF WHICH MATCHES THE CONICAL BORE OF THE FRONT RING TO ENTER THE SAME, AND A RADIALLY ENLARGED INTERMEDIATE PORTION WITH RADIALLY EXTENDING TEETH, SAID EXPANSIBLE RING HAVING A BORE WHICH AT THE END ADJACENT THE STOP RING IS TAPERED AND MATCHES THE OTHER OF THE CONICAL SURFACES OF THE STOP RING TO RECEIVE THE SAME, SAID EXPANSIBLE RING INCLUDING AN EXTERNALLY TAPERED PORTION AT AN END ADJACENT THE NUT RING AND EXTERNAL PROTRUSIONS EXTENDING TOWARDS THE OTHER END, SAID EXPANSIBLE RING BEING PROVIDED WITH SLITS EXTENDING AXIALLY FROM THE END ADJACENT THE STOP RING TOWARDS THE OTHER END, SAID NUT RING HAVING AN INNNER BORE WITH A PORTION REMOTE FROM THE EXPANSIBLE RING WHICH IS THREADED FOR ENGAGING A BOLT AND A PORTION ADJACENT THE EXPANSIBLE RING WHICH IS TAPERED TO MATCH THE TAPERED PORTION OF THE EXPANSIBLE RING TO RECEIVE THE SAME, SAID NUT RING HAVING SLITS EXTENDING AXIALLY FROM THE END ADJACENT THE EXPANSIBLE RING TOWARDS ITS OTHER END. 